Double sideband amplitude modulation

[UA_student]

Hi,

 I'm using Labview to control Agilent 33xxx series waveform generator. I need to generate a double sideband amplitude modulated signal. I used the example given in the NI Labview Hardware input/output examples. However when I run the program I see a single sideband amplitude modulated waveform. Any suggestions?

[Lea_D]

Hi UA_student,

Can you please give a bit more information about the example you are using. I went to help»Find Examples » Hardware Input and Output... then where did you go? Also, are you using a specific driver? What version of LabVIEW are you using. It's possible that the example is only meant for single sideband.

I downloaded the Agilent Technologies 33XXX series signal generator and am looking at the Generate Modulated Waveform.vi example in there. It looks like this would be for single ended modulation.

Hope this helps!

[UA_student]

Hi Mr. Lea D,

 Thanks for the reply. I'm using Labview 2010 and Agilent 33120A waveform generator. And I'm using the same example you mentioned (Generate Modulated Waveform.vi). I was expecting to see a double sideband modulation. I was not sure whether I'm missing any of the setting.

 Also if the example is for single sideband modulation, is there an example for double sideband modulation.

Thanks,

[Lea_D]

Hi UA,

If you get a chance, look through the block diagram of this example. The inputs and settings that you put through an intialize subVI. This initialize sets all of the settings and clears the buffer. iIt then makes sure that it's using the correct device since it's an Agilent 33XXX instead of specific driver for the 33120A.

Next it goes into a box called configure standard waveform. In this block it sets the freqnecy, amplitude and DC offset that you specify. It turns this into a string command and then writes it to your function generator. If you look in the next block in the example, this is where the modulation occurs. There is an area that takes the modulation freqency that you put in and formats it into the string for the VISA write.

Since this is just an Agilent device conneted to your computer, you are probably not actually transmitting or recieving anything. Are you using this waveform generator to make your carrier frequency? What are you trying to recieve a double sideband modulation signal for? I don't see any pre-existing examples for double sideband modulation currently.